Is this normal?

Sure its normal. 174 millimeters or 17.4 centimeters is just under 7 inches long, no? Actually, I was very close if not exactly the same size at 13.5.
However, it isn't normal. There isn't anything wrong with it, but it is bigger than the average college male's is. It is avobe average, which isn't normal, but it sertainly isn't bad.
Look, you still have about 5 more years to develop. You will head into adulthood with a very long, nice cock. Don't stress out about the size of it, just enjoy it. *no one besides yourself should be using it until then*. I stressed about it for a while, then I thought, ah, whatever. Just enjoy what you've been given!

BTW, if you are like me (which you might not be), I ended up with around 9.5 inches, give or take an inch. It depends on the day. Warm: 10. Cold: 9. You will like it, and your wife/girlfriend will too!